They do, and to be honest, first time I watched eps, I missed it sometimes. Like I remember I said a couple of months ago that I don't think Grissom appreciates Greg, or something along the lines of he's a bit mean to him. But after all your comments, I watched quite a few episodes again, and noticed that Grissom does appreciate him/is proud of him, and just tried to push him to get the best out of himself. I can't remember what ep i watched the other night and it just was totally obvious to me.